Is GTK expected to adhere to Font KCM preferences?

rokejulianlockhart · October 6, 2025, 11:12am

I have reported github.com/kolunmi/bazaar/issues/298, under the presumption that GTK already adheres to it, for it appears to elsewhere. However, the developer appears to believe that it doesn’t:

github.com/kolunmi/bazaar

`kcm_fonts`'s preferences are not adhered to by 0.3.0.

opened 05:04PM - 01 Sep 25 UTC

closed 01:41AM - 06 Oct 25 UTC

RokeJulianLockhart

bug help wanted

#### How To Reproduce 1. ~~~sh #!/usr/bin/env sh sudo dnf5 install kf6-kc…mutils-6.17.0-1.fc42.x86_64 && \ kcmshell6 kcm_fonts ~~~ 1. Configure all typeface categories to 10 be pt: <img width="1023" height="898" alt="Image" src="https://github.com/user-attachments/assets/4dfbb9f8-b6f9-43e4-8daf-ba53e0d2f99a" /> 1. ~~~sh #!/usr/bin/env sh sudo dnf5 install flatpak-1.16.1-1.fc42.x86_64 && \ flatpak install https://dl.flathub.org/repo/appstream/io.github.kolunmi.Bazaar.flatpakref && \ flatpak update app/io.github.kolunmi.Bazaar/x86_64/stable --commit=6daa321bb5f07c2b6f41fea787011bfc12ec48ae67bef5b4339bf2a679099576 && \ flatpak run app/io.github.kolunmi.Bazaar/x86_64/stable ~~~ #### The Consequence 1. The "Install" button's label is < 10 pt: <img width="1276" height="796" alt="Image" src="https://github.com/user-attachments/assets/9caa22d4-7790-4a3f-86d1-281509967e91" /> 1. The headings are > 10 pt: <img width="1276" height="796" alt="Image" src="https://github.com/user-attachments/assets/06bbb1ae-9d93-4455-80ef-0350f9e397f6" /> #### My Environment ~~~sh #!/usr/bin/env sh flatpak info app/io.github.kolunmi.Bazaar/x86_64/stable ~~~ <blockquote> ~~~YAML ID: io.github.kolunmi.Bazaar Ref: app/io.github.kolunmi.Bazaar/x86_64/stable Arch: x86_64 Branch: stable Version: 0.3.0 License: GPL-3.0-or-later Origin: flathub Collection: org.flathub.Stable Installation: system Installed: 28.6 MB Runtime: org.gnome.Platform/x86_64/48 Sdk: org.gnome.Sdk/x86_64/48 Commit: 6daa321bb5f07c2b6f41fea787011bfc12ec48ae67bef5b4339bf2a679099576 Parent: ed778db3e72d77ccfc5cc3509d084bb122c9de3242c56f8bac8590b8333119cb Subject: Merge pull request #7 from flathub/update-master-d487891 (e1100d4a1f8b) Date: 2025-08-31 22:22:55 +0000 ~~~ </blockquote> ~~~sh #!/usr/bin/env sh rpm -qi flatseal ~~~ <blockquote> ~~~YAML Name : flatseal Version : 2.3.1 Release : 1.fc42 Architecture: noarch Install Date: Fri 01 Aug 2025 16:01:26 BST Size : 625042 Signature : RSA/SHA256, Thu 24 Apr 2025 23:50:42 BST, Key ID c8ac4916105ef944 Source RPM : flatseal-2.3.1-1.fc42.src.rpm Build Date : Thu 24 Apr 2025 23:48:22 BST Build Host : buildvm-ppc64le-13.iad2.fedoraproject.org Packager : Fedora Project Vendor : Fedora Project URL : https://github.com/tchx84/Flatseal Bug URL : https://bugz.fedoraproject.org/flatseal ~~~ </blockquote> ~~~sh #!/usr/bin/env sh rpm -qi flatpak ~~~ <blockquote> ~~~YAML Name : flatpak Version : 1.16.1 Release : 1.fc42 Architecture: x86_64 Install Date: Mon 09 Jun 2025 20:14:30 BST Size : 6836181 Signature : RSA/SHA256, Mon 12 May 2025 11:06:32 BST, Key ID c8ac4916105ef944 Source RPM : flatpak-1.16.1-1.fc42.src.rpm Build Date : Mon 12 May 2025 10:54:00 BST Build Host : buildhw-x86-08.iad2.fedoraproject.org Packager : Fedora Project Vendor : Fedora Project URL : https://flatpak.org/ Bug URL : https://bugz.fedoraproject.org/flatpak ~~~ </blockquote> ~~~sh #!/usr/bin/env sh rpm -qi $(rpm -qf $(command -v kcmshell6)) ~~~ <blockquote> ~~~YAML Name : kf6-kcmutils Version : 6.17.0 Release : 1.fc42 Architecture: x86_64 Install Date: Sun 10 Aug 2025 15:03:09 BST Size : 1186009 Signature : RSA/SHA256, Fri 08 Aug 2025 19:42:03 BST, Key ID c8ac4916105ef944 Source RPM : kf6-kcmutils-6.17.0-1.fc42.src.rpm Build Date : Mon 04 Aug 2025 00:56:47 BST Build Host : buildvm-x86-18.rdu3.fedoraproject.org Packager : Fedora Project Vendor : Fedora Project URL : https://invent.kde.org/frameworks/kcmutils Bug URL : https://bugz.fedoraproject.org/kf6-kcmutils ~~~ </blockquote>

Consequently, they recommended that I refile with GTK. I don’t want to file something totally irrelevant to them, so before I do so, I want to confirm that this isn’t, instead, a fault of kde-gtk-config, because reddit.com/r/kde/comments/4fvug4/comment/d2csqpo explains that kcm_fonts’ preferences are (mostly) stored inside ~/.config/kdeglobals, which GTK shouldn’t care about. Can anyone confirm?

ngraham · October 6, 2025, 10:02pm

The font is synced to some GTK thing somewhere, it isn’t only stored in kdeglobals. I don’t remember which thing it is though.

Overall, this is “best effort” territory.

rokejulianlockhart · October 6, 2025, 10:49pm

@ngraham, I meant as an authoritative source. I believe that GTK consumes CSS3 stylesheets, so it would need to be duplicated elsewhere, if so. However, does that mean that this compatibility is provided by gtk-kde-config, rather than GTK4 itself?